12,436 research outputs found
Conductivity of Mono- and Divalent Cations in the Microporous Zincosilicate VPI-9
Impedance spectroscopy is used to investigate the long-range ionic conductivity of the microporous, zincosilicate VPI-9 (Si/Zn = 4.0) (International Zeolite Association framework type VNI) containing the alkali cations Li^+, Na^+, K^+, Rb^+, and Cs^+, and the alkaline earth cations Mg^(2+), Ca^(2+), and Sr^(2+). Monovalent cation-exchanged samples Li- and Na-VPI-9 lose X-ray crystallinity upon vacuum dehydration at 450 °C, whereas K-, Rb-, and Cs-VPI-9 remain crystalline and exhibit conductivities of 1.7 × 10^(−4), 3.5 × 10^(−4), and 4.9 × 10^(−4) S/cm, respectively, at 450 °C and activation energies of 0.72, 0.64, and 0.69 eV, respectively, in the temperature range 150−450 °C. Divalent cation-exchanged sample Mg-VPI-9 also loses X-ray crystallinity, but Ca- and Sr-VPI-9 remain crystalline and exhibit conductivities of 2.3 × 10^(−6) S/cm and 7.7 × 10^(−7) S/cm, respectively, at 450 °C, and activation energies of 0.88 and 0.91 eV, respectively, over the temperature range 150−450 °C. When compared to aluminosilicate zeolite X (Si/Al = 1.25) exchanged with the same cations, all crystalline M-VPI-9 materials have greater conductivities than M-X, with the exception of K-X (1.6 × 10^(−3) S/cm at 450 °C), with the greatest differences arising between the divalent exchanged materials. Dense, crystalline zincosilicate samples with the compositions K_2ZnSi_xO_(2(x+1)) (x = 2−5), Rb_2ZnSi_5O_(12), and Cs_2ZnSi_5O_(12) are also prepared and characterized for comparison with the microporous materials and exhibit much lower conductivities than their microporous counterparts at the same composition
A New Test of Issue Ownership Theory: U.S. Senate Campaign Debates
This study tests issue ownership theory on U.S. Senate debates. Issue ownership theory states that each of the two major American parties possess issues which the public perceive to be best handled by one party over another. Republicans are thought to be better at handling problems concerning national defense, foreign policy, and taxes. Democrats are believed to be better at addressing issues such as education, health care, and the environment. This study hypothesizes that, due to unique characteristics regarding the office being sought, U.S. Senate candidates from both major parties do not adhere to previously recognized patterns of issue ownership and more frequently discuss Democratic issues over Republican issues. The results of content analytic programing provided supporting evidence for this hypothesis. Based on this analysis, the extent to which issue ownership applies to debates is dependent upon the position being sought
The Establishment-Level Behavior of Vacancies and Hiring
This paper is the first to study vacancies, hires, and vacancy yields at the establishment level in the Job Openings and Labor Turnover Survey, a large sample of U.S. employers. To interpret the data, we develop a simple model that identifies the flow of new vacancies and the job-filling rate for vacant positions. The fill rate moves counter to aggregate employment but rises steeply with employer growth rates in the cross section. It falls with employer size, rises with worker turnover rates, and varies by a factor of four across major industry groups. We also develop evidence that the employer-level hiring technology exhibits mild increasing returns in vacancies, and that employers rely heavily on other instruments, in addition to vacancies, as they vary hires. Building from our evidence and a generalized matching function, we construct a new index of recruiting intensity (per vacancy). Recruiting intensity partly explains the recent breakdown in the standard matching function, delivers a better-fitting empirical Beveridge Curve, and accounts for a large share of fluctuations in aggregate hires. Our evidence and analysis provide useful inputs for assessing, developing and calibrating theoretical models of search, matching and hiring in the labor market.
The establishment-level behavior of vacancies and hiring
The authors study vacancies, hires, and vacancy yields (success rate in generating hires) in the Job Openings and Labor Turnover Survey, a large representative sample of U.S. employers. The authors also develop a simple framework that identifies the monthly flow of new vacancies and the job-filling rate for vacant positions, the employer counterpart to the job-finding rate for unemployed workers. The job-filling rate moves counter to employment at the aggregate level but rises steeply with employer growth rates in the cross section. It falls with employer size, rises with the worker turnover rate, and varies by a factor of four across major industry groups. The authors' analysis also indicates that more than 1 in 6 hires occur without benefit of a vacancy, as defined by JOLTS. These findings provide useful inputs for assessing, developing, and calibrating theoretical models of search, matching, and hiring in the labor market.Employment ; Labor market
Recruiting Intensity during and after the Great Recession: National and Industry Evidence
We measure job-filling rates and recruiting intensity per vacancy at the national and industry levels from January 2001 to September 2011 using data from the Job Openings and Labor Turnover Survey. Construction makes up less than 5 percent of employment but accounts for more than 40 percent of the large swings in the job-filling rate during and after the Great Recession. Leisure & Hospitality accounts for nearly a quarter of the large drop in recruiting intensity during the Great Recession. We show that industry-level movements in job-filling rates and recruiting intensity are at odds with the implications of the standard matching function in labor search theory but consistent with a generalized function that incorporates an important role for recruiting intensity per vacancy.
The nature and effects of political party culture on political careers
Previous scholarship on the political cultures of the political parties provides anecdotal evidence regarding the distinct differences between the two major U.S. political parties. This conventional wisdom is based on one important essay authored by Jo Freeman nearly 30 years ago. To date, our understanding regarding the nature and effects of the political cultures of the Democratic and Republican parties suffers from lack of rigorous empirical examination. This study explores the political cultures of the political parties by examining the behaviors of congressional members seeking their party's nomination for another office. In this dissertation, I measure the extent which the Democratic and Republican parties' political cultures effect progressively ambitious members of the U.S. Senate and U.S. House of Representatives. In addition, I provide firsthand accounts of how these cultures impact state legislative careers. The empirical tests I present in this project largely support Freeman's earlier accounts as to the nature of the two major parties' political cultures at the national level. Based on firsthand accounts, however, I also provide evidence to suggest the political cultures of the parties are subject to short-term, localized forces at the state-level
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LGBTQ+ Health-a Novel Course for Undergraduate Students.
The concept of providing focused, competency-based LGBTQ+ health education outside the setting of health professional programs, specifically for undergraduates, is quite uncharted. However, the issue at the core of our rationale is one shared by those with and without clinical exposure: how to best support the development of cultural competence in providers who are or will be caring for LGBTQ+ patients. Traditional health professional education programs have enacted a number of curricular initiatives in this regard, designed for advanced learners. By focusing specifically on the undifferentiated learner, we offer a new perspective on the timing of LGBTQ+ health-related education. Our course is not intended to supplant the critical learning and application that must occur in the clinic or hospital room. Rather, we present a framework for cultivating understanding of the healthcare issues faced by the LGBTQ+ community that may help a learner to acquire and apply skills subsequently with greater cultural competence
Rockdale County MSP grant annual evaluation report: year two
Issued as final reportRockdale County (Ga.) School
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